title: Dietary aspartyl-phenylalanine-1-methyl ester delays osteoarthritis and prevents associated bone loss in STR/ORT mice.
abstract: OBJECTIVE
  STR/ORT mice provide a well-known model for murine idiopathic OA, with histological joint lesions resembling those of human OA. This model was used to investigate protective effects of the dipeptide aspartyl-phenylalanine-1-methyl ester (Asp-Phe-OMe or aspartame) via the oral route vs a regular diet.
  
  
  METHODS
  STR/ORT mice were housed individually and fed diets with or without Asp-Phe-OMe (4 mg/kg), after weaning at the age of 3 weeks, until 15 months of age (average of 20 animals per group). The study groups were kept blinded to the investigators, who measured food consumption and body weight and performed gait mobility tests. Radiographic scans were also performed at regular time intervals to evaluate differential radiographic anomalies associated with progress of OA in response to oral Asp-Phe-OMe therapy.
  
  
  RESULTS
  The Asp-Phe-OMe-fed animals presented a pattern of significantly delayed disease onset. In addition, their muscle and bone mass were highly preserved, even at later time points after OA was established. Moreover, control animals presented a higher variability in gait motility in comparison with the Asp-Phe-OMe-fed animals, suggesting a protective effect from movement limitations associated with advanced OA.
  
  
  CONCLUSIONS
  Asp-Phe-OMe, given orally, delays OA in the spontaneous STR/ORT model, improves bone cortical density and muscle mass, and may contribute to a better quality of life for these diseased animals.
authors.affiliation: Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.
authors.forename: Carl V
authors.initials: CV
authors.lastname: Manion
authors.forename: Ute
authors.initials: U
authors.lastname: Hochgeschwender
authors.forename: Allen B
authors.initials: AB
authors.lastname: Edmundson
authors.forename: Tony E
authors.initials: TE
authors.lastname: Hugli
authors.forename: Claudia R
authors.initials: CR
authors.lastname: Gabaglia
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001218:Aspartame / Q000008:administration & dosage*; D019587:Dietary Supplements; D004195:Disease Models, Animal; D005260:Female; D016014:Linear Models; D008124:Locomotion / Q000187:drug effects; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D018482:Muscle, Skeletal / Q000187:drug effects; D010003:Osteoarthritis / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology; D010024:Osteoporosis / Q000150:complications / Q000517:prevention & control*; D011859:Radiography; D011897:Random Allocation; D012016:Reference Values
chemical_list: D001218:Aspartame